In M2M communication environments, each entity acquires basic configuration information through pre-provisioning, registers in an M2M system/service using the information and then uses the M2M service. Here, a registration procedure is performed one-to-one between a registree entity and a registrar entity. The registree sends a request message for using services to other entities through the registrar.
However, when the registree moves and thus does not directly send a request message to the registrar, that is, when the registree needs to transmit the request message through another entity, problems are generated. In this case, the entity does not deliver the request message to a target entity because the request message is not sent from a registree of the entity. To solve this problem, the registree may be registered with the entity. However, when the registree is registered with a new entity, the entity ID of the registree may be changed. Since the registree can access resources in an M2M system only using the previous ID, the registree has a problem in use of services if a new ID is assigned thereto through new registration. Furthermore, when the registree cancels previous registration and registers with a new entity, child resources of service resources previously used by the registree are deleted along with cancellation of previous registration and thus the registree cannot use the child resources.
Accordingly, the present invention proposes a method through which a registree can continuously use services without registering with other entities even when the registree moves.